Dorcus mexicanus, Benesh, 1944

Paulsen, M. J., 2010, Stag beetles of the genus Dorcus MacLeay in North America (Coleoptera, Lucanidae), ZooKeys 34 (34), pp. 199-207 : 202

Dorcus mexicanus

Examination of the type specimens of D. mexicanus revealed that they are Dorcus parallelipipedus (L.), a Palearctic species. The identical male genitalia (Fig. 11), protruding clypeus of males, irregularly punctate elytra, and bituberculate frons of the female provide overwhelming evidence to support this conclusion. Thus, the name D. mexicanus Benesh is here reduced to a synonym of D. parallelipipedus (new synonymy).

Coincidentally, I encountered a second pair of D. parallelipipedus recently accessioned at the FMNH that bore handwritten labels indicating “ Mexico, Nuevo Leon, Monterey (sic), Aug 1976 ”. The presence of a second, more recent pair of D. parallelipipedus from Mexico at first suggested that the species might be introduced there. However, on further examination I found that other handwritten locality labels of the same style from the accessioned collection were erroneous (with incorrect countries). While it is not impossible that the species is adventive in Mexico, it is more likely given the nomenclatural history of Dorcus that the common D. parallelipipedus has been mislabeled in these two instances.